甲状腺功能减退症对成年期大鼠前额叶皮质Syntaxin-1蛋白表达的影响

目的研究成年期甲状腺功能减退症(简称甲减)大鼠前额叶皮质内突触前膜蛋白syntaxin-1的表达,探讨甲减脑损伤可能的分子机制。方法用丙基硫氧嘧啶(6-n-propyl-2-thiouracil,PTU)诱导建立成年期大鼠甲减模型,采用放射免疫法测定甲减组和健康对照组大鼠的血清甲状腺激素水平,免疫组织化学方法分析两组大鼠前额叶皮质内Syntaxin-1的表达。结果甲减组大鼠血清T3、T4水平[(0.34±0.04)nmol/L、(43.01±2.95)nmol/L]显著低于健康对照组[(0.65±0.52)nmol/L、(55.20±3.56)nmol/L](P<0.05);前额叶皮质Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ层Syntaxin-1的表达水平显著低于健康对照组(P<0.01)。结论成年期甲减大鼠前额叶皮质内Syntaxin-1表达减少。

Effect of hypothyroidism on the Syntaxin-1 expression in the prefrontal cortex of adult rats

Objective To observe the expression of syntaxin-1 in prefrontal cortex of adult-onset hypothyroidism rats in order to explore the molecular mechanism of brain injury of hypothyroidism. Methods All 30 adult male Sprague-Dawley rats were separated into 2 groups randomly：Hypothyroidism group （ n = 15） and control normal group （ n = 15）. The hypothyroidism models were replicated with 6-n-propyl-2-thiouracil （ PTU）. The levels of serum T3,T4 were assayed by radioimmunoassay method,and the level of syntaxin-1 in prefrontal cortex was analyzed by im-munohistochemistry. Results In the Hypothyroidism group,the levels of serum T3 and T4 were significantly lower than those in the control normal group （ P 0. 05） ; and the levels of Syntaxin-1 protein in theⅠ、Ⅱ、Ⅲ、Ⅳ、Ⅴof layers prefrontal cortex were significantly lower compared to the control normal group （ P 〈0. 01）. Conclusion The expression of syntaxin-1 in the prefrontal cortex of adult-onset hypothyroidism is decreased.